Valve bag



May 12, 1936. J. A. ROSMAIT VALVE BAG Filed April 26, I935 e/afin 4.Fdsma/Z ATTORNEYS.

Patented May 12,- 1936 UNITED STATES PATENT OFFICE VALVE BAG John A.malt, Manistee, Mich.

Application April 26, 1935, Serial No. 18,311

10 Claims.

bags and particularly to multi-wall paper bags of the valve type.

An object is to provide a bag of this character with a valve controllingthe filler opening, which valve is constructed to effectively close theopening against leakage.

A further object is to provide a valve bag which may be formed from atube without wastage of the material and wherein the valve structure isformed of material separate from the material of which the bag walls areformed and is arranged in the shape of a tube to serve as an extensionof the valve opening through the bag walls and is adapted to effectivelyseal such opening under the pressure of the bag contents.

In bags of this character the bag walls are generally folded inwardly atone corner to form the valve opening and my improved valve extendsinteriorly of the bag as a tubular continuation of such opening and to asubstantially greater distance than the extension of such infolded comerportions of the bag walls. This valve tube extension is preferablyslitted beyond the iniolded corner portions of the bag walls to providea passageway for the discharge of the material with which the bag isfilled into the interior of the bag.

A meritorious characteristic is the provision of a valve tube structureformed of a plurality of separate individually flexible and individuallvfree laminations of sheet material arranged in overlapping shin ledrelat onshi and beingindividually of different length. and withsuccessive laminations being of successivel increased length from thevalve o ening downwardly within theba whereby these several lamin ationsare adapted o be individually cmmp a ainst the bag Walls to seal theintake openin Other objects. advanta es. and meritorious features of myimproved structure will more fully appear from the followingspecification. a pended claims. and accompanying drawing. wherein:

"Figure 1 is a side elevation of a fragment of a bag partly bro-ken awayembodying my invention,

Fig. 2 is a plan of the sheet which is used to form the valve in the bagof Fig. 1,

Fig. 3 is a cross-sectional view taken on line 33 of Fig. 1,

Fig. 4 is a cross-sectional view taken on line 4-4 of Fig. 1,

Fig. 5 is a side elevation of a fragment of the bag partly broken awayembodying my invention in a slightly modified form,

Fig. 6 is a perspective of a slightly modified form of sheet used tomake the valve,

Fig. 7 is a perspective of a second modified form of sheet used to makethe valve, and

Fig. 8 is an elevation of a fragment of a bag 5 partly broken awayembodying my invention in a slightly modified form.

My invention is adapted for use in bags which are provided with valveopenings through which the contents of the bag are deposited within the10 bag to fill the same. The valve is so constructed that under theinfluence of the content material it functions to close the filleropening and prevent leakage of the content material. These bags arecommonly formed of paper and the paper 15 wall of the bag is generallyof a multi-ply character. Bags of this type are widely used in thecement and lime industry and the content ma.-v terial is in a powderform. It is deposited in the bag through filling mechanism whichembodies a tubular discharge spout that is adapted to be receivedthrough the filler opening. The spout serves to distend the valvestructure and the valve structure, which is of a tubular form, closelyhugs the outside of the spout so that any appreciable leakage ordischarge during the filling operation is not permitted. Ordinarily theair which is within the bag escapes through the paper wall of the bagduring the filling of the bag though specific provision may be made forits escape. My improvement is shown in connection with a multi-wallpaper bag ofthe non-gusseted type. The two side walls are fastenedtogether at the bottom of the bag and at the top of the bag and at onecorner these side walls are turned inwardly and provided with a valveopening.

In the several figures of the drawing the bag wall is indicated at III.In Fig. 1, l2 indicates a plurality of laminations which go to make upthe 40 wall of the bag. In this figure in order 'to eliminate theshowing of a. large number of laminations at the valve the bag wall isthere illustrated as if it were of a single layer, but it is to beunderstood that the ordinary practice is to provide a wall of aplurality of layers and this also applies to Figs. 5 and 8. These bagsare generally formed from a paper tube which is cut off at suitablelengths and the opposite walls stitched together at the top and bottomto form the bag. The upper portion only of the bag is here shown but theconstruction of the lower half is the same except that the upper half isprovided with the valve opening which is omitted from the lower half. Itis conventional practice which is well understood.

In the figures of the drawing the two side walls are shown as securedtogether along the end by a line of stitching i4 and at one corner theseside walls are turned inwardly as at It providing. a valve controlfiller opening through which a spout of a suitable filling machine maybe inserted. This spout is shown in dotted outline in Figs. 1, 5 and .8.

The inturned corner portion I6 01 the side walls are relatively stiffdue to the fact that the bag walls are formed of several laminations ofstrong tough paper suitable for carrying a substantial weight. Myinvention resides in the provision of auxiliary means which is securedwithin the bag in the described relationship with the inturned cornerportion l6 and which serves to seal the valve filler opening against theescape of the content material of the bag. This valve structure isformed of a suitable sheet or sheets of flexible material, such aspaper, which may have the general shape shown in Fig. 2 wherein onesheet is indicated as I 8. This sheet of material is folded upon itselfand its two edges are brought together between the upper edges of theside walls of the bag and stitched in place therebetween by the line ofstitching M. This sheet is so disposed.

within the bag that it freely encircles the inturned corners It as shownin Figs. 1, 5, and 8.

This valve structure is formed of a plurality of individually separate,superimposed, flexible sheets l8 which forma multi-wall valve structurewherein each of the',s'everal laminations is individually free andindividually flexible so that they serve to be easily crumpled orcrushed against the side walls ofthe bag to block escape of the bagcontent through the filler opening. The manner in which valve structuresare crushed against the side walls of the bag by the action of thecontents thereof, so as to close the filler opening, is well understoodas the art has been extensively developed and there is no illustrationshowing this well understood functioning. Fig. 3 shows the valvedistended with the filler spout therein and Fig. 4 shows the bag emptiedwith the valve structure as it might then be disposed.

Preferably the valve structure extends into the bag a substantialdistance beyond the end of the inturned comer portion and is slitted asat 20 for a portion of its length spaced inwardly from the inturnedcorner It to permit the discharge that individually they may respond tobe crushed against the side walls to seal the valve opening againstleakage and will respond much more easily than if the three laminationswere into.- grally connected. They possess substantially a greaterdegree of flexibility than the inturned corner portion it of the bagwalls.

In Figs. 5 to 8, inclusive, the several layers which make up the valveper so are shown as being of diflerent length and as arranged in anoverlapping shingled relationship. These layers are indicated in Fig. 5as 22, 24, and 28. In this structure the two longer layers only areslitted and thelongest layer is arranged underneath so that it wouldtend to be crushed upwardly over the two innermost layers to form aneffective closure .and the valve structure itself is increasinglyflexible from the inturned comer portion interiorly of the bag. Thistype 01 shingled overlap is shown in Fig. 6 where the same layers aresimilarly numbered.

Fig. '7 illustrates a reversal of the construction of Fig. 6 with thelongest layer being arranged on top instead of on the bottom. Fig. 8illustrates a slightly modified form of construction wherein the valvestructure is cut on an angle as shown which increases the tendency toreadily crush against the side walls of the bag to seal the filleropening. In this construction each of the layers is slitted, though todiiierent lengths, and the layers'are indicated as 28, I0, and 32.

this type of structure there is no wastage of material in themanufacture of the bags due to the fact that the bag tube from hichsections are severed to form the bags may be cut straight across. Thevalve structure is formed of separate pieces which are secured in placeas shown. The tubular valve element forms an extension of the inturnedcomer portion of the bag and telescopes at one end thereover but issupported entirely from the line of stitching which secures the sidewalls of the bag together. It is highly flexible but readily deformed toseal the valve filler opening. In the preferred form it is in creasinglyflexible as it extends from the inturned corner portion of the baginteriorly thereof.

What I claim:

1. A valve bag having its opposite side walls secured together along oneend except for a short distance at one comer, said side walls inturnedat such corner providing a valve opening, a sheet of material foldedupon itself and having its iuxtaposed edges secured together betweensaid side walls by the line of securement thereof forming.

at one corner forming a valve opening, a valve tube secured within saidbag to form a tubular extension over said opening and itself formed of aplurality of superimposed individually free and individually flexiblelaminations, said laminated tube being slitted lengthwise along itslower edge spaced from the valve opening.

3. A valve baghaving its side walls inturned at one corner forming avalve opening, a valve tube secured within said bag to form a tubularextension over said opening and itself formed of a plurality ofindividually flexible laminations arranged in shingled overlappingrelationship with the individual laminations having individuallydiil'erent tubular lengths.

4. A valve bag having its side walls inturned at one comer forming avalve opening, a valve tube secured within said bag to form a tubularextension over said opening and itself formed of a plurality ofindividually flexible laminations arranged in shingled overlappingrelationship with successive laminations being of successively increasedtubular length.

5. A valve bag having its side walls inturned at.

one corner forming a valve opening, a .valve tube secured within saidbag to form a tubular extension over saidopening and itself formed of aplulaminated tubular extension downwardly within the bag.

6. A valve bag having a filler opening on one side adjacent to thecorner of the bag, a valve tube arranged within the bag forming atubular extension of said opening and comprising a plurality 'oflarninations of sheet material-arranged in superimposed shingledrelationship, the several laminations being individually flexible and ofrelatively varying length.

7. A valve bag having a filler opening on one side adjacent to thecorner of the bag, a valve tube arranged within the bag forming atubular extension of said opening and comprising a plurality oflaminations of sheet material arranged in superimposed shingledrelationship, the several laminations being individually flexible and ofrelatively varying length, and the lamination of greatest length beingslitted lengthwise along its lower edge spaced from the filler opening.

'8. A valve bag having its side walls inturned atone corner forming avalve-opening, a valve tube secured within said bag to form a. tubularextension over said opening and itself formed of a plurality ofindividually flexible laminations arranged in shingled overlappingrelationship with certain laminations being slitted for a portion oftheir lengthfrom the end within the bag toward the valve opening.

9. A valvebagshaving its side walls inturned at one corner forming avalve opening, a valve tube secured within such bag to form a tubularextension of such opening and received at one end over said inturnedcorner, said valve tube comprising a plurality of individually flexiblelaminations arranged in shingled o'verlappingrelationship, thesuccessive laminations from the interior of the tube downwardly withinthe bag being of successively greater length, and the lamination ofgreatest length being provided with an opening along its lower edgeadjacent to but spaced inwardly from the end of the inturned corner ofthe bag. I

10. A valve bag having its side walls inturned at one corner forming afiller opening, a sheet of flexible material folded upon itself andsecured within the bag surrounding said inturned corners of the bagsidewalls and projecting interiorly of the bag as a tubular' extensionof said filler opening, said tubular extension having a thickness at itsend spaced :interiorly from said inturned comer substantially less thanits thickness adjacent to said corner.

JOHN A. ROSMAIT.

